There are many different types of machines used to make cuts in previously formed and hardened concrete and asphalt. For example, slab saws make generally vertically-oriented cuts and can be used for a variety of purposes, such as cutting trenches in concrete for laying pipe and/or cables, renovation projects in which a worn or broken surface may need modification and/or replacement, and other projects in which a concrete or asphalt surface needs to be cut.
Self-propelled slab saws are well known. FIGS. 1 and 2 show diagrammatical side views of an existing self-propelled slab saw 1. The saw 1 includes a saw blade 2 that could be mounted on either a right arbor or left arbor for cutting concrete and/or asphalt or other surface. An engine 3 operates the saw blade 2 and could be used to drive one or more of the wheels 4. The operator walks behind the saw 1 and controls the saw's forward/backward direction and speed using a lever 5. Typically two handles 6 extend from the saw 1 to allow the operator to manually maneuver the saw 1.
With the saw blade 2 raised above the concrete as shown in FIG. 1, the operator will need to maneuver the saw 1 to the cut site and manually align the saw blade 2 with the intended cut path using the handles 6 and lower the blade 2 as shown in FIG. 2. The operator will then engage the drive wheels 4 using the lever 5 to drive the saw 1 forward along the cutting path. One issue that arises during operation is keeping the saw blade aligned with the cutting path. The operator will generally attempt to cut along a straight path. Typically, the operator will need to manually adjust the saw blade by exerting force on the handles 6 to steer the blade 2 back on course. This requires a certain amount of physical strength to maneuver the heavy saw and tends to cause injuries due to overexertion of the operator. When the saw cut is finished, the blade 2 is moved to the next cut site by maneuvering the saw 1 using the handles 6.
Another issue that arises is difficulty in moving the slab saw to the work site and/or propelling the drive wheels over certain surfaces. For example, it is difficult to move the heavy slab saw across a dirt path to the work site because the wheels tend to sink into the dirt. Irregular surfaces also create difficulties in moving the saw to the work site. For example, the wheels of a typical slab saw will have difficulty being propelled over a gravel path. If the surface is slick, the drive wheels 4 will tend to slip and not propel the saw. A surface containing holes, such a potholes or a trench for laying pipe, can also pose difficulties for the slab saw to traverse.